Resistivity ρ=JE=neυdE=neμ1
μ= mobility
ρ=1019×1.6×10−19×1.61=2.561Ωm
=0.4Ωm
JEE Main 2019 — Physics Electromagnetism
Mobility of electrons in a semiconductor is defined as the ratio of their drift velocity to the applied electric field. If, for an N-type semiconductor, the density of electrons is 1019m−3 and their mobility is 1.6m2V−1s−1, then the resistivity of the semiconductor (since it is an N-type semiconductor contribution of holes is ignored) is close to:
Held on 9 Jan 2019 · Verified 6 Jul 2026.
0.2Ωm
4Ωm
2Ωm
0.4Ωm
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